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a little while ago I build a simple amp for my telly using those output transformers I got from Magnus and the 12B4A, also from Magnus. I did like the sound of the 12B4A's a lot. The amp I had to take apart for the tube sockets, they are now in my new amp with the 4 GU32, but I got more sockets yesterday so I can build another one of those little amps, this time I want to build a bit a better amplifier, using a better filtered power supply, DC heating and a real pre stage. And I am gonna paint the output transformers nicely black My aim is 1 to 1,5 watts pure triode power, that must be to archive with this setup. Anybody got any suggestions, feel free. One of the cigar boxes, I already prepared for tube amplification, sanded the prints away (took a long time of sanding) and painted it with clear coat many times, it has now a nice closed surface.

Attachment:

12B4A amp.jpg

Attachment:

Cigar boxes.jpg

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Hi guys, so now everything is painted, cool. I will wait over night to have everything dry enough to handle. Not having cut any holes into the case for the tubes, I get second thoughts, maybe I use different tubes, instead of 12B4A I could use a GU50 in triode mode and just choose a tap on my output transformers, that has the least distortion. That would give me like 5 watts or so. Could that work? Any suggestions are welcome.

Well, here is the beginning with the high voltage transformer in place. Now I gotta let everything dry overnight and tomorrow I will put that thing together, I got most of the parts in house, missing a couple of caps and resistors, as usually.

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Hi, Ben!Of course, 12B4A,.... Output and main transf. on Your box are very small for GU50./GU50 needs for SE 400v, 100 ma, fixed-Ubias 30-35v, or very power Rk , 12,6 v and output transf. 10-12 sq.sm/.

Hallo everybody, here are the pictures of the latest development. Much more I cannot do today, I am missing parts, as usually, not many, just a couple of resistors and caps. But here is how it's gonna look like, not bad for a days worth of work, I suppose, 24 hours ago that was just an empty cigar box with company name burned into the wood all around.

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